Scientists at New York University collected pathogen samples taken from the lungs of 589 patients with severe COVID-19 who were connected to a ventilator. The researchers also identified a separate subgroup of 142 patients who underwent bronchoscopy to clear the airways to determine the number of viral particles in the lungs and the possible presence of secondary infections.
It turned out that in the deceased patients, the viral load in the lower respiratory tract was about ten times higher compared to the number of SARS-CoV-2 particles in those who survived. There was also no indication that the virus could force the immune system to attack its own tissues. But at the same time, all deceased patients have an average of 50% reduced production of proteins, which are part of the immune response aimed at “remembering” pathogens.
“Our results show that the body’s inability to cope with the large number of viruses infecting the lungs is largely responsible for the deaths from COVID-19. If we can identify the source of this problem, it will allow us to find an effective treatment aimed at strengthening the body’s own defenses, ”the authors of the study said.
At the same time, scientists did not find any evidence that the cause of the death could be an associated bacterial infection, but it may have been associated with the use of antibiotics at an early stage of treatment.
Earlier, scientists from the UK have assessed the volume and feasibility of taking antibiotics for patients with COVID-19. Among the 49,000 hospitalized patients included in the analysis, at least 85% received one or more antibiotics during inpatient treatment, of which 37% received these drugs before hospitalization.
The biggest discovery was that bacterial infections in patients with COVID-19 were quite rare and were not specific to the coronavirus. As a rule, these were common nosocomial infections, and cases of secondary infection were detected mainly in patients of the intensive care unit and not earlier than 48 hours after hospitalization.